PROJECT SUMMARY, Core A: Husbandry and Management Core Expanded SPF (eSPF) rhesus macaques (Macaca mulatta), which are defined as being negative to rhesus rhadinovirus, simian immunodeficiency virus, simian foamy virus, simian T-lymphotropic virus, simian retrovirus, macacine herpesvirus-1 (BV), measles, and rhesus cytomegalovirus, are necessary to study an increasing range of viruses important to human health, as well as the development and testing of novel viral vectors. eSPF macaques have become the premier animal model for HIV/AIDS research, including studies on HIV pathogenesis, AIDS-related opportunistic infections, and the development of HIV treatments and vaccines. Currently, the national need for genetically characterized eSPF rhesus macaques for HIV/AIDS research far exceeds the current availability. Therefore it is imperative that the available eSPF rhesus macaque populations grow in size. The successful maintenance of expanded SPF colonies is challenging, however, and requires strict management practices in order to remain specific pathogen free. With over 18 years? experience in establishing and maintaining a colony of eSPF animals, the ONPRC is the leader at managing eSPF rhesus macaques. The overall aims of the Husbandry and Management Core are to breed and grow the ONPRC eSPF colony in order to meet existing and future animal resource demands, continue to provide and improve upon the existing exemplary eSPF husbandry and veterinary care, and to improve the eSPF resource by making the entire colony lymphocryptovirus negative. To do this we will provide innovative team based management practices including expansion of the colony into outdoor sheltered housing, introduction of a time- mated breeding program and artificial insemination, a foster mother program for abandoned infants, implementation of new enrichment and social monitoring strategies, and re-derivation of LCV negative infants from within the eSPF colony.